That’s why the proposal of immutable relations, User.where! would raise a ActiveRecord::ImmutableRelation but must be a way to create mutable relations, Model.all would be fine since it returns new relations on each call (not sure about internals but it seems not too difficulty to make it work):
irb(main):012:0> Transaction.all.object_id => 70363740246020 irb(main):013:0> Transaction.all.object_id => 70363740260420 An “acceptable" API would be: User.where!(email: ‘b...@example.com’) #=> raise ActiveRecord::ImmutableRelation(“You can’t use bang relation methods directly on model, use User.all.where! instead”) User.all.where!(email: ‘b...@example.com’) #=> [] Cheers, Gabriel Sobrinho gabrielsobrinho.com On Nov 5, 2013, at 11:31 AM, Allen Madsen <allen.c.mad...@gmail.com> wrote: > The primary reason I would be against these being public is the following > example: > > User.where!(email: 'b...@example.com') > > Reading that, I would expect that I have changed the default scope for EVERY > user query. I believe this is what José Valim was hinting at. Because the > ActiveRecord class is a global object, scopes originate from there, and any > piece of code could modify the behavior of that global, it would introduce > side effects throughout an application. Ideally, when side effects are > present, they're localized to a small scope. > > Allen Madsen > http://www.allenmadsen.com > > > On Tue, Nov 5, 2013 at 7:55 AM, Gabriel Sobrinho <gabriel.sobri...@gmail.com> > wrote: > França, > > I'm too late to the party, I thought these bang methods was public on rails 4 > :( > > We will have people doing wrong things with these methods but a good > documentation will reduce that, ruby itself have a lot of these methods like > params.merge!(..) or controller_name.gsub!(...) and I never saw people (that > do not means there is no people reporting, I just don't saw) reporting issues > because things like that. > > The problem of scopes that must not be mutated can be solved using some > freeze implementation on that scope, like this: > > relation = User.where(:dumb => false).immutable! > relation.where!(:dumb => true) > #=> raises ActiveRecord::ImmutableRelation > > I agree that new developers may do strange things but the rails itself is not > so easy for beginners, but I have no expertise about how it may impact the > community, so if you guys think that won't be great these methods be public, > :okaymeme: > > > Gary, > > What I usually do when "mutable relations" makes sense are filters like that: > https://gist.github.com/sobrinho/7318585 > > > On Monday, November 4, 2013 1:01:59 PM UTC-2, Rafael Mendonça França wrote: > Yes, there is > https://github.com/rails/rails/commit/8c2c60511beaad05a218e73c4918ab89fb1804f0#commitcomment-2211685 > > Rafael Mendonça França > http://twitter.com/rafaelfranca > https://github.com/rafaelfranca > > > On Mon, Nov 4, 2013 at 11:53 AM, Gabriel Sobrinho <gabriel....@gmail.com> > wrote: > França, > > There is a reason for that? They sound useful in a lot of scenarios. > > On Wednesday, October 30, 2013 2:02:54 PM UTC-2, Rafael Mendonça França wrote: > The bang methods are private and should not be used in applications (see the > :nodoc: in the method definition) > > Rafael Mendonça França > http://twitter.com/rafaelfranca > https://github.com/rafaelfranca > > > On Wed, Oct 30, 2013 at 1:51 PM, Gary Weaver <garys...@gmail.com> wrote: > I understand that bang methods in the classic Ruby sense are supposed to > alter the current instance, but getting errors like: > > NoMethodError: undefined method `where!' for #<Class:0x007ff1522d3110> > > and > > NoMethodError: undefined method `includes!' for #<Class:0x007ff1522d3110> > > when calling the bang methods from QueryMethods on a model class are really > not helpful. > > It's understandable that you don't want to pass a model class into a method > that expects a relation that it can act upon and change with a bang query > method and have it successfully create a new relation and call some method on > it that is never again seen, hence the error. I also understand wanting to > avoid any more checking/raising code than necessary in ActiveRecord both for > maintainability, clarity, and maybe efficiency- but just look at this: > > 2.0.0p247 :001 > MyModel.to_s > => "MyModel" > 2.0.0p247 :002 > MyModel.new.to_s > => "#< MyModel:0x007fc92aa017e8>" > 2.0.0p247 :003 > MyModel.where({}) > => ... > 2.0.0p247 :003 > MyModel.where!({}) > NoMethodError: undefined method `where!' for #<Class:0x007fc92a95a240> > > Thanks! > > > -- > You received this message because you are subscribed to the Google Groups > "Ruby on Rails: Core" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to rubyonrails-co...@googlegroups.com. > To post to this group, send email to rubyonra...@googlegroups.com. > > Visit this group at http://groups.google.com/group/rubyonrails-core. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- > You received this message because you are subscribed to the Google Groups > "Ruby on Rails: Core" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to rubyonrails-co...@googlegroups.com. > To post to this group, send email to rubyonra...@googlegroups.com. > Visit this group at http://groups.google.com/group/rubyonrails-core. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- > You received this message because you are subscribed to the Google Groups > "Ruby on Rails: Core" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to rubyonrails-core+unsubscr...@googlegroups.com. > To post to this group, send email to rubyonrails-core@googlegroups.com. > Visit this group at http://groups.google.com/group/rubyonrails-core. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- > You received this message because you are subscribed to a topic in the Google > Groups "Ruby on Rails: Core" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/rubyonrails-core/4YusNsRI4Kk/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > rubyonrails-core+unsubscr...@googlegroups.com. > To post to this group, send email to rubyonrails-core@googlegroups.com. > Visit this group at http://groups.google.com/group/rubyonrails-core. > For more options, visit https://groups.google.com/groups/opt_out. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Core" group. 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